Current work vehicles, such as tractors and other agricultural vehicles, include an engine and a transmission, such as a power shift transmission (PST) or a continuously variable transmission (CVT), rotatably coupled to the engine. In addition, work vehicles typically include an electronic controller that is configured to control the operation of both the engine and the transmission to achieve desired operation. For example, an operator may provide an input to the controller selecting a desired ground speed for the work vehicle. Based on the operator input, the controller may be configured to automatically control the operation of the engine and/or the transmission such that the actual speed of the work vehicle matches the desired speed selected by the operator.
Additionally, work vehicles often include a power take-off (PTO) that is used to provide power to various implements, such as mowers, balers, forage harvesters and spreaders. Typically, PTOs are selectively connectable to a source of rotational power, such as the vehicle's engine, by a clutch that is configured to be automatically controlled via the electronic controller of the work vehicle. To date, many PTO clutch control systems have been developed that operate under a variety of control strategies designed to provide suitable functionality.
When engaging a PTO clutch, it is often necessary to achieve a relatively high torque (often referred to as the breakaway friction torque). In certain instances, this breakaway friction torque may be higher than the maximum available engine torque. When engine loads are relatively low, there is typically enough time to approach the peak engine torque and slide over the maximum engine torque curve to allow the breakaway friction torque to be reached during the clutch engagement process. However, with relative high engine loads, there is typically insufficient time to achieve the breakaway friction torque, which results in stalling of the engine without any engagement of the PTO clutch.
Accordingly, an improved system and method for providing adaptive incremental control of the engagement of a PTO clutch for a work vehicle in order to accommodate increased engine loads while preventing engine stall would be welcomed in the technology.